Physics-
General
Easy
Question
A cylindrical container of length L is full to the brim with a liquid which has mass density 
. It is placed on a weight scale; the scale reading is w. A light ball which would float on the liquid if allowed to do so, of volume V and mass m is pushed gently down and held beneath the surface of the liquid with a rigid rod of negligible volume as shown on the left. If instead of being pushed down by a rod, the ball is held in place by a thin string attached to the bottom of the container as shown on the right. What is the tension T in the string?
–m)g
g
- mg
- none of these
–m)g
g
The correct answer is: –m)g
F = T + mg Þ Vg = T + mg \ T = (V – m)g
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